The present disclosure relates to a transceiver circuit, to a method for tuning resistor settings of a communication system, in particular a communication system with two capacitively coupled transceivers, and to a method for communication between two capacitively coupled transceivers.
In modern communication systems, communication channels between a transceiver sending data and a transceiver receiving the data can be implemented by means of capacitive coupling, also known as AC coupling. In particular, in systems where the transceivers are attached to mobile devices and therefore the coupling is necessarily detachable, capacitive coupling may be more suitable than for example an ohmic coupling.
In a detachable capacitively coupled communication system, capacitance values between the transceivers may undergo variations, for example due to variations of distances or orientations of capacitor plates establishing the capacitive coupling, environmental parasitics or other variations.
On the receiver parts of the transceivers, commonly resistors form the capacitive coupling together with the capacitors. Therein, the resistors commonly have fixed resistance values. Due to the variations in the capacitances, for the fixed resistance values, a transceiver may be not capable of receiving a data package without errors. As a result, and also due to possible clock mismatches, a synchronization between the transceivers may be lost. This may be particularly relevant if self-clocking signals are to be transmitted. The de-synchronization may for example increase during data transmission and communication failures may occur. Furthermore, the variations in the capacitances may be different for different applications and/or environmental conditions.